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Finding the Fourth Proportional to 639.95, 958.10 and 423.09

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Solution

The fourth proportional to 639.95, 958.10 and 423.09 is: 633.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.95 : 958.10 = 423.09 : x
  2. Step 2: Convert to fraction form
    639.95/958.10 = 423.09/x
  3. Step 3: Cross multiply
    639.95x = 958.10 × 423.09
  4. Step 4: Simplify right side
    639.95x = 405,360.41
  5. Step 5: Solve for x
    x = 405,360.41/639.95
  6. Step 6: Final answer
    x = 633.43

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.